Door latch assembly



Feb. 17,1970 I A. R. SNOW 3,495

' DOOR LATCH ASSEMBLY Filed Sept. 15, 1967 3 Sheets-Sheet 1 ALBERT R. SNOW EDWARD D. OBQ/A/V ATTORNEY Feb.,l 7, 1970 mud-w 8,4 I boon Luca ASSEMBLY 3 Sheets-Sheet 2 Filed Se pt. 15, 1967 INVENTQR A 1.5527 R. Suaw /02 5 Eon A20 D. OPE/Au ATTORNEY Ere. 6.

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7 I nbon LATCH ASSEMBLY Fil ed Sept. 15, 1967 3 Sheets-Sheet s lA/l/E/VZOR ALBEETA. 5A/0W EDWARD D. OER/AN Arraevgr United States Patent US. Cl. 292-74 13 Claims ABSTRACT OF THE DISCLOSURE A door latch assembly of the so-called touch plate type is disclosed. This assembly includes a barrel, a bolt slidably mounted in the barrel so as to be capable of being moved between a retracted and an extended position and biasing means urging the bolt away from the retracted position into the extended position. The assembly also includes holding means adapted to engage the bolt so as to hold it in an extended position, urging means for biasing the holding means so that it will automatically engage and to hold the bolt in the extended position, locking means for preventing the holding means from being operative for its intended purpose and at least one release means for releasing the holding means from the bolt. The release means used may include a so-called touch plate type of structure.

BACKGROUND OF THE INVENTION Latch structures have been used for centuries. Practically all of such structures which are in common use today involve an assembly of parts including at least one door handle, a barrel located within a door and a bolt mounted within the barrel so as to be capable of being moved upon actuation of the door handle. Usually these structures or assemblies include a spring biasing the bolt so that it extends from the barrel used. With structures such as this the bolt is designed so as to be capable of being directly moved through a direct mechan ical connection with the handles. Generally the bolt is moved from an extended position to a retracted position when the handle is turned, although structures are known in which a bolt is moved by a wedge-like action when a handle is pushed.

No one can deny that door latch assemblies or structures of the broad types indicated in the preceding discussion have proved effective. However, in spite of this it is considered that there is a commercial need for new and improved door latch assemblies having a different mode of operation than various structures or assemblies as are briefly indicated in the preceding. Frequently individuals affected by various types of physical ailments cannot satisfactorily manipulate a conventional door handle so as to operate it in a convenient manner. There is a need for door latch assemblies which can be easily and conveniently operated by many such individuals.

Frequently a conventional door latch assembly is not acceptable or desirable to a user merely because it operates in a conventional manner or has a conventional type of appearance. There is a need to provide door latch assemblies which will be acceptable to such users in place of more conventional structures. There is also a need for door latch assemblies having a different mode of operation than conventional structures for many applications where the mode of operation of conventional door latch assemblies is undesirable.

SUMMARY OF THE INVENTION A broad generalized object of the present invention is to provide new and improved door latch assemblies meeting these commercial needs. Thus, an object of the inven- See tion is to provide door latch assemblies having a different mode of operation than conventional structures in this field. A related object of the invention is to provide door latch assemblies which can be easily and conveniently used by persons suffering various types of physical handicaps. Another related object of the invention is to provide door latch assemblies which are desirable merely because of their unique mode of operation, and the unique structural appearances they can have because of such operation.

Further objects of this invention are to provide new and improved door latch assemblies which may be manufactured relatively easily at a comparatively nominal cost, which may be installed relatively easily, which may be easily and conveniently used in various applications, which are capable of giving long, reliable performance, and which are capable of being easily serviced as required.

These various objectives of the invention are achieved in door latch assemblies, each of which include a barrel, a bolt mounted within the barrel so as to be capable of being moved between a retracted and an extended position and biasing means urging the bolt away from the retracted position into the extended position. In a latch assembly of this invention these parts are used with a holding means which is capable of engaging the bolt so as to hold it in an extended position and urging means biasing the holding means so that the holding means will lock the bolt in the extended position, preferably locking means for preventing the holding means from being operative for its intended purpose, and at least one release means for causing the holding means to be disengaged from the bolt so that the bolt may be moved to its retracted position, as on opening the door latch assembly.

DESCRIPTION OF THE DRAWING The aforegoing objects and various other objects of this invention and advantages of it will be apparent from a detailed consideration of the accompanying drawings in which:

FIG. 1 is a side-elevational view showing one side of a door latch assembly of this invention;

FIG. 2 is a side elevational view similar to FIG. 1 showing the other side of this door latch assembly;

FIG. 3 is a top plan view of this same door latch assembly;

FIG. 4 is an end view of the door latch assembly illustrated in the preceding figures;

FIG. 5 is a partial cross-sectional view taken at line 55 of FIG. 1;

FIG. 6 is a partial cross-sectional view taken at line 6-6 of FIG. 4;

FIG. 7 is a cross-sectional view corresponding to FIG. 6 showing the bolt in a retracted position;

FIG. 8 is a partial cross-sectional view taken at line 8-8 of FIG. 7;

FIG. 9 is an exploded view showing all parts of the door latch assembly illustrated in the preceding figures in isometric projection;

FIG. 10 is an end view of a modified door latch assembly of this invention, this view being partially in section so as to illustrate the features of it which are different than the features of the preceding door latch assembly;

FIG. 11 is an end view of a modified bolt and barrel being capable of being used with either of the door latch assemblies illustrated in the preceding figures;

FIG. 12 is a side view of a part of the bolt and barrel illustrated in FIG. 11; and

FIG. 13 is a side view of a jamb plate for use with the bolt and barrel indicated in FIGS. 11 and 12.

3 DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS The invention is best explained with reference to the accompanying drawings. Here there is shown a door latch assembly of the present invention. This assembly includes a centrally located cylindrical barrel 12 which holds a bolt 14 so that the bolt 14 may be moved between an extended position as shown in FIGS. 1, 2, 3, 4 and 6 and a retracted position as shown in FIG. 7. It also includes mounting knobs 16 and 18 which are in the nature of handles.

The mounting knob 16 is provided with an internal cylindrical cavity 20 within which there is pivotally mounted a disc 22 by means of a pin 24. This pin 24 extends across the cavity 20. A small lever arm 26 used in rotating the disc 22 is attached to the disc 22 so as to extend therefrom in a downward direction. This arm 26 can be considered as a handle in the operation of the entire assembly 10. Another similar, but fixed arm 28- is attached to the knob 18 so as to extend downwardly therefrom. This arm 28 can also be considered as a handle because of its use during the operation of the complete assembly. The knob 18 is provided with an internal cylindrical cavity 30 corresponding to the cavity 20.

Within the cavity 30 in the knob 18, there is located a pressure plate 32. This plate 32 is dimensioned so that it can be moved along the length of the cavity 30 generally towards the bolt 14 and the barrel 12. The plate 32 carries an extending shaft 34 having a threaded end 36 upon which there is located a retaining nut 38. If desired a Washer 40 may be associated with this nut 38. The shaft 34 extends through what may be considered a mounting bracket 42 attached to and associated with the knob 18 so as to extend into a small cavity 44 within this bracket 42.

A conventional coil spring is located between the bracket 42 and the piate 32 for the purpose of biasing this plate 32 to an outward position with respect to the central part of the assembly. If desired the spring 46 may terminate in an annular retaining groove 48 in the plate 32. With this construction the plate 32 may be pushed inwardly against the pressure of the Spring 46 so as to move a rod 50 generally towards the barrel 12. This rod 50 is guided by moving through a guide hole 52 in the bracket 42. The rod 50 may be attached to the plate 32, but does not have to be attached to this plate.

A similar but related structure is utilized Within the cavity 20. Here there is located another plate 54 which is capable of being slid within the cavity 20 generally towards the barrel 12 and the bolt 14. This plate 54 is biased away from the bolt 14 and the barrel 12 by means of a conventional coil spring 56. The spring 56 may be held in place by having its ends located within a small depression 58 in the plate 54 and another depression 60 in a bracket 62. The brackets 42 and 62 are used for substantially the same purpose. Upon examination of the drawing it will be seen that the bracket 62 is formed integrally with the mounting knob 16'. The plate 54 also carries a rod 64 corresponding to the rod 50 previousiy described. This rod 64 projects through a guide opening or hole 66 in the bracket 62 generally towards the barrel 12 and the bolt 14.

Hollow tubular spacers 68 are attached to the bracket 62 so as to extend therefrom into contact with the bracket 42. These two brackets and the parts connected to them and mounted on them are secured together in proper alignment through the use of screws 70 extending through the spacers 68. These spacers 68 in effect serve to maintain a proper spacing between the brackets 42 and 62 so that the entire assembly 10 may be easily secured together in an operative manner. When the brackets 42 and 62 are secured together in this manner a curved surface 72 on the bracket 42 engages a part of the barrel 12 while another corresponding curved surface 74 on the bracket 62 engages an opposed part of the barrel 12 so as to adequately support this barrel. Movement of the barrel 12 with respect to the brackets 42 and 62 when the barrel 12 is so mounted is prevented by small pins 76 on the brackets 42 and 62 fitting within corresponding small openings 78 in the barrel 12.

The barrel 12 has a normally open end 80' and a normally closed end 82 which is adapted to be closed by a cap 84. This cap 84 may be conveniently secured to the closed end 82 through the use of a retainer pin 86 which fits through holes 88 in the barrel 12 and through a hoie 90 in the cap 84. The cap 84 carries a centrally located guide shaft which extends from the cap 84 along the axis of the barrel 12. A small coil spring 102 is located around this shaft so as to bias or urge the bolt 14 generally away from or out of the barrel 12 by engaging an end plate 104 on this bolt 14. The end plate 104 is provided with a centrally located opening 106 which accommodates the shaft 100. The shaft 100 also carries a smaller shaft 108 which extends along the axis of the barrel 12 within the central region of the barrel 12.

The bolt 14 includes a latch end 110 which is joined to the end plate 104 by means of two shafts 112. These shafts 112 are located on diametrically opposite sides of the axis of the barrel 12. The latch end 110 also carries what can be referred to as lock shafts 11 4 which extend from this end 110 parallel to the axis of the barrel towards the end plate 164. These lock shafts 114 are dimensioned so that when the bolt 14 is in an extended position as indicated in FIG. 6, they terminate adjacent to the small shaft 108. When the bolt 14 is in a retracted position these lock shafts 114 extend past the small shaft 108 as indicated in FIG. 7 of the drawing to generally along the shaft 100.

The bolt 14 is restrained so that it will only move between these two positions by a small pin 116 located within a hole 118 in the latch end 110 fitting into an elongated slot 120 in the barrel 12. This slot 120 extends in a straight line parallel to the axis of the barrel 12. The slot not only serves to limit movement of the bolt 14, but also serves in part to prevent twisting or rotation of the bolt 14 within the barrel 12. Such twisting or rotation of the bolt 14 is also prevented by means of an auxiliary stabilizing rod 122.

This rod 122 extends from the cap 84 parallel to the shaft 10!) through a hole 124 in the end plate 104. This hole 124 is larger than the rod 122 and is dimensioned so as to correspond in shape to the shape of an end 126 of a locking rod 128. This locking rod 128 has another end 130 and is of a somewhat shaft-like appearance; it projects through the interior of the bolt 14 and a hole 132 in the latch end 110.

It will be realized from an examination of the initial seven figures of the drawing that this locking rod has two positions which are referred to hereinafter as locking position and non-locking position. In the locking position the lock rod 128 extends from the bolt 14 as indicated in FIG. 7 of the drawing. In the non-locking position, the locking rod 128 is located so that the end 130 is generally within the plane of a tapered latch surface 134 on the latch end 110.

This latch end 110 is also provided with another tapered surface 136 and the two surfaces are joined by a vertically extending edge 138. These surfaces 134 and 136 in effect define on the bolt 14 a vertically extending Wedge shaped end. The lock rod 128 is held so as to be biased in the locking position by means of a small coil spring 140 located around the rod 122 so as to push against cylinder 142 attached to and forming a part of the end 126 of the rod 128 in such a manner as to in eifect form a part of this end 126. It will be recognized that the hole 124 is dimensioned so as to correspond to the dimensions of the entire end 126 including the cylinder 142.

The function of the lock rod 128 is related to the operation of a small double-ended trigger or lever 144. This lever 144 is provided with a centrally located hole 146 fitting around the small shaft 108 in such a manner so as to pivotally mount this lever 144. The lever 144 is dimensioned so as to extend across the center of the bolt 14 and the barrel 12 so as to have ends 148 and 150 which may be viewed through top and bottom openings 152 in the barrel 12. These openings 152 are adjacent to the rods 50 and 64, and these rods normally extend through them so that the rod 50 engages the end 148 and so that the rod 64 engages the end 150. The lever 144 is normally biased into a position in which such engagement occurs by another spring 154 engaging the end 148, urging this end away from the bracket 62. For the purpose of retaining the spring 154 a cup-like retainer 156 is formed on the bracket 62, and a small projection 158 is located on the end 148. The spring 154 fits around this projection 158 and into the retainer 156.

The assembly may be easily installed on a door such as a door 160 as indicated in phantom in FIGS. 1 and 2 of the drawing. Prior to assembly the barrel 12 and the bolt 14 and the various associated parts are assembled together in the manner indicated. Also, the knob 18 is assembled as described in the preceding. The knob 16 is left disassembled to the extent that there is nothing located within the cavity 20. With assemblies of these parts in hand, an appropriate hole (not numbered) of a size necessary to accommodate the barrel 12 is drilled from the edge 162 of a door such as the door 160 perpendicular to such an edge midway between the sides of the door. Next, an appropriate other hole (not numbered) of a dimension suitable to receive the brackets 42 and 62 is drilled between the sides of the door perpendicular to the first hole.

Then, the barrel 12 (and the associated parts mounted on it) is inserted in the hole drilled to receive this barrel. Thereafter, the knob 18 is located against the door 160 into operative contact with the barrel 12 so that the pins 76 engage the openings 78. The mounting knob 16 is then similarly placed into position, and the two knobs 16 and 18 are attached through the use of the screws 70, securing the entire assembly 10 together. Next, the plate 54 and the spring 56 in the knob 16 are inserted to a position as shown in FIG. 5 so that the spring 56 is held under compression. Then the disc 22 is placed in the location shown in FIGS. 1, 3 and 5 and the pin 24 is inserted across the knob 16 so as to hold this disc 22 in place, retaining the plate 54 and the spring 56 within the knob 16. At this point, the entire assembly 10 is ready for use.

During such use, the door 160 normally will be moved to an operating position against a conventional jamb plate 164 so as to first engage a surface 166 of this plate, such as a jamb plate 164 as shown in FIG. 3 of the drawing. Engagement of the surface 136 with this jamb plate 164 will cause the bolt 14 to slide within the barrel 12 from the extended position shown in FIG. 6 and other figures of the drawing to the retracted position shown in FIG. 7. This action will occur because when the locking rod 128 is in its locking position (as it normally is when a door is open) the end of the cylinder 124 is against one of the lock shafts 114 so as to prevent movement of the lever 144 to a position as shown in FIG. 5. As a result of this, the bolt 14 will be free to move forward within the barrel 12. The position of the lever 144 when the bolt 14 is in its retracted position is indicated in FIG. 7 of the drawing.

As the bolt 14 is moved to its retracted position it will be apparent that this spring 102 is compressed, and this spring 102 will automatically function to return the bolt 14 into its extended position when the pressure of contact with the jamb plate 164 is relieved. It is so returned normally when the entire assembly 10 is located so that the bolt 14 extends through the conventional hole 168 in the jamb plate 164. In this position the door 160 could be opened by continuing the rotation of this doorin the same direction as it was moved into contact with the jamb plate 164, causing compression of the bolt 14 within the barrel 12. If it were not for the lock rod 128 the door 160 equipped with the assembly 10 could also be opened by being moved in a direction in reverse to the direction it was moved in order to be closed. From this it will be seen that a structure having utility as a door closure assembly can be manufactured omitting the lock rod 128 and the various parts associated with it as described in the preceding.

Normally when the door 160 is closed contact with a curved tab 167 on the jamb plate 164 will cause the lock rod 128 to slide within the bolt 14 to what has been identified in the preceding as a non-locking position. In this non-locking position the cylinder 142 is spaced from the lock shaft 114 it previously engaged. As a result of this spacing, the spring 154 will be operative to rotate the lever 144 to a locking position as shown in FIGS. 5 and 6 of the drawing. In this position the end 148 of the lever 144 is located between the cylinder 142 and one of the lock shafts 114 and the end 150 is behind the other lock shaft 114. As a result of this, the bolt 14 is locked in its extended position so as to be held against retraction.

Since the lever 144 moves into a position in which the bolt 14 cannot be retracted and is held in an extended position this lever 144 and the associated structure necessary for its operation can be considered as a holding means for holding the bolt 14 in an extended position. Similarly the spring 154 may be classified as an urging means for biasing the lever 144 or holding means so that it automatically engages the bolt 14 in order to hold the bolt in the extended position.

With the assembly 10, the bolt 14 may be only retracted from such an extended position by lifting upon the lever arm 26 or pushing in upon the plate 32. When either of these things is done, the lever 144 will be rotated from its locking position as described because of movement of either the rod '50 or the rod 64. In effect these rods 50 or 64 constitute means for rotating the lever 144 to a position in which this lever 144 is out of the way as far as the movement of the bolt 14 is concerned. Thus, a door such as a door may be pulled open, or pushed open, when either the arm 26 or the plate 32 has been actuated as indicated.

Then a door such as the door 160 may be moved away from a jamb plate such as the jamb plate 164 so as to open. As this occurs the bolt 14 slides to its retracted position within the barrel 12. Because of the functions and operations of rods 50 and 64 and the various parts associated with them such as the arm 26 and the plate 32 serving to cause movement of the lever 144, these rods 50 and 74 and such associated parts may be referred to as release means. It will be realized that for certain installations only one of these release means is necessary. To achieve the method of operation described the wedge shape of the surfaces 134 and 136 of the latch end 110 of the bolt 14 is necessary.

In FIG. 10 of the drawing there is shown a modified door latch assembly of the present invention which is exceedingly closely related to the assembly 10. For this reason, various parts of the assembly 170 which are the saame as or substantially the same as various corresponding parts of the assembly 10 are not separately described herein, and are indicated where necessary herein and in the drawing by the same numerals previously used to describe such parts.

In the assembly 170, the mounting knob 16 is replaced by a closely related mounting knob 172 having an internal cavity 174 located therein which corresponds to the cavity 20 previously described. This cavity holds a slidable plate 176 similar to the plate 32 previously described. This plate carries a rod 178 which is similar to and serves the same function as the rod 64 previously described. A coil spring 180 corresponding to and serv- 7 ing the same function as the spring 56 is located between the plate 176 and a bracket 182. The bracket 182 is the same as the 'bracket 62 previously described. The plate 176 is held within the cavity 174 so as to be capable of being moved :by virtue of an elongated screw 184 extending through a fiat slot 186 in the plate 176.

The modified door latch assembly shown in FIG. 10 is mounted and used in substantially the same manner as the assembly 10. However, during such mounting the screw 184 is placed in position as the last step in order to secure the plate 176 in place while in the assembly 10 the pin 24 is the last part inserted to assemble the device. The plate 176 is, of course, pushed so as to operate as a release means.

In FIGS. 11, 12 and 13 of the drawing, there is shown a manner in which the bolt 14 within the barrel 12 can be modified in order to achieve a door latch assembly in which the door can be swung in either direction. In this particular case, the various parts are the same as the part described in conjunction with the assembly 10. Hence, they are designated in the drawing and herein by the same numerals previously used.

In this particular case, a slot 186 extends across the surfaces 134 and 136 and the edge 138 of the latch end 110 on the bolt 14. This bolt 14 is adapted to be used with a jamb plate 192 as shown in FIG. 13 of the drawing. This jamb plate 192 has instead of the usual opening, a V-shaped center portion 194 which is of a complementary shape to the shape of latch end 110. A projection 196 is located within this center portion 194 so as to engage and depress the locking rod 128 when the bolt 14 illustrated in FIGS. 11 and 12 is in place with respect to this jamb plate 192, causing the locking rod 128 to be moved to a position where the bolt 14 is locked against movement in the manner previously described.

Those skilled in the art to which this invention pertains will realize that a number of changes may be made in the precise door latch assemblies shown without departing from the basic features or characteristics of this invention. As an example of this, conventional lock structures may be mounted in various ways upon either a mounting knob such as the mounting knob 16 or the mounting knob 18 in order to prevent movement of a structure such as the disc 22 or the plate 32. When such movement cannot occur, obviously, the complete assembly with which such a lock is used cannot be opened because the bolt of such an assembly is held in an extended position by a structure previously described. Various other structural changes may be made in the assemblies described and illustrated through the use or exercise of routine engineering skill or ability.

I claim:

1. A door latch assembly having a barrel with an open end, said barrel being adapted to be mounted in a door so that said open end is adjacent to an edge of said door, a bolt slidably mounted in said barrel so as to be capable of being moved between an extended position in which said bolt extends from said open end of said barrel and a retracted position in which said bolt is located within said barrel, and biasing means for urging said bolt away from said retracted position into said extended position, wherein the improvement comprises:

holding means for holding said bolt in said extended position, said holding means being movable between a position in which said holding means engages said bolt so as to hold said bolt in said extended position and a position in which said holding means disengages said bolt, permitting said bolt to be moved to said retracted position,

said holding means comprising a lever means capable of being rotated to a position in which said lever means engages said bolt so as to prevent movement of said bolt,

urging means for biasing said holding means so that said holding means automatically engages said bolt to hold said bolt in said extended position when said bolt is in said extended position,

at least one release means for releasing said holding means from said bolt when said bolt is held by said holding means in said extended position so that said bolt may be moved to said retracted position,

said release means comprises means for rotating said lever means so as to cause said lever means to be rotated out of engagement with said bolt,

said bolt having a wedge shaped end, enabling said bolt to be moved from said extended position to said retracted position by contact with a door jamb, and at least one knob means adapted to be located on an exposed surface of the door and wherein, said release means includes movable means mounted on said knob mean and rod means actuated by said movable means, said movable means contacting said lever means during movement of said movable means to rotate said lever means.

2. A door latch assembly as claimed in claim 1 including:

spring means holding said movable means in a position in which said lever means is not engaged by said release means.

3. A door latch assembly having a barrel with an open end, said barrel being adapted to be mounted in a door so that said open end is adjacent to an edge of said door, a bolt slidably mounted in said barrel so as to be capable of being moved between an extended position in which said bolt extends from said open end of said barrel and a retracted position in which said bolt is located within said barrel, and biasing means for urging said bolt away from said retracted position in said extended position, wherein the improvement comprises:

holding means for holding said bolt in said extended position, said holding means being movable between a position in which said holding means engages said bolt so as to hold said bolt in said extended position and a position in which said holding means disengages said bolt, permitting said bolt to be moved to said retracted position,

urging means for biasing said holding means so that said holding means automatically engages said bolt to hold said bolt in said extended position when said bolt is in said extended position,

at least one release means for releasing said holding means from said bolt when said bolt is held by said holding means in said extended position so that said bolt may be moved to said retracted position, said bolt having a wedge shaped end, enabling said bolt to be moved from said extended position to said retracted position by contact with a door jamb,

locking means for preventing said holding means from holding said bolt in said extended position,

said locking means being located so as to be automatically actuated by contact with a door jamb so as to permit said holding means to hold said bolt in said extended position during operation of said door latch assembly,

said holding means comprising lever means capable of being rotated to a position in which said lever means engages said bolt so as to prevent movement of said bolt,

said release means comprises means for rotating said lever means so as to cause said lever means to be rotated out of engagement with said bolt,

at least one knob means adapted to be located on an exposed surface of the door and wherein:

said release means includes movable means mounted on said knob means and rod means actuated by said movable means, said movable means contacting said lever means during movement of said mOVable means to rotate said lever means.

4. A door latch assembly as claimed in claim 3 ineluding:

spring means holding said movable means in a position in which said lever means is not engaged by said release means.

5. A door latch assembly as claimed in claim 3 wherein said locking means comprise:

a rod slidably mounted in said bolt so as to be capable of being moved between a locked position in which said rod extends from said bolt and a non-locking position in which said rod fits generally within said bolt, and

spring means biasing said rod so that it is normally located within said locking position,

said rod being located so as to be capable of being engaged by a part of a door jamb during the use of said door latch assembly and moved to said nonlocking position by contact with said door latch assembly.

6. A door latch assembly as claimed in claim 5 wheresaid holding means comprises lever means capable of being rotated to a position in which said lever means engages said bolt so as to prevent movement of said bolt.

7. A door latch assembly as claimed in claim 6 wheresaid release means comprises means for rotating said lever means so as to cause said lever means to be rotated out of engagement with said bolt.

8. A door latch assembly as claimed in claim 7 including:

at least one knob means adapted to be located on an exposed surface of the door and wherein,

said release means includes movable means mounted on said knob means and rod means actuated by said movable means so as to be capable of contacting said lever means during movement of said movable means so as to cause rotation of said lever means.

9. A door latch assembly having a barrel with an open end, said barrel being adapted to be mounted in a door so that said open end is adjacent to an edge of said door, a bolt slidably mounted in said barrel so as to be capable of being moved along an axis between an extended position in which said bolt extends from said open end of said barrel and a retracted position in which said bolt is located within said barrel, and biasing means for urging said bolt away from said retracted position into said extended position, two knobs connected to said barrel, said knobs being adapted to be mounted on opposite sides of said door, wherein the improvement comprises:

said knobs being secured to said barrel so as to be incapable of relative movement with respect to said barrel;

holding means for holding said bolt in said extended position, said holding means being movable between a position in which said holding means engages said bolt so as to hold said bolt in said extended position and a position in which said holding means disengages said bolt, permitting said bolt to be moved to 10 said retracted position, said holding means being a lever pivotally mounted so as to rotate about an axis transverse to the axis of the bolt;

urging means for biasing said holding means so that said holding means automatically engages said bolt to hold said bolt in said extended position when said bolt is in said extended position;

a separate release means for releasing said holding means from said bolt so as to permit said bolt to be moved to said retracted position from said extended position carried by each of said knobs, each of said release means being capable of being moved with respect to the knob upon which it is located so as to separately actuate said holding means;

said bolt having a wedge-shaped end enabling said bolt to be moved from said extended position to said retracted position by contact with a door jamb.

10. A door latch assembly as claimed in claim 9 wheresaid holding means comprising a lever means capable of being rotated to a position in which said lever means engages said bolt so as to prevent movement of said bolt.

11. A door latch assembly as claimed in claim 10 wherein:

each of said release means comprises means for rotating said lever means so as to cause said lever means to be rotated out of engagement with said bolt.

12. A door latch assembly as claimed in claim 9 including:

a locking rod means for preventing operation of said holding means, said locking rod means being movably mounted in said bolt, said locking rod means being capable of being moved in said bolt between first and second positions, in said first position said locking rod means being in a position to block engagement of said holding means so that said bolt is capable of being moved to said retracted position, in said second position said locking rod means permitting said bolt to be engaged by said holding means so as to hold said bolt in said extended position.

13. A door latch assembly as claimed in claim 12 including:

a door jamb, said door jamb having projection means for engaging said locking rod upon closure of said door so as to move said locking rod means to said second position when said bolt engages said door jamb.

References Cited UNITED STATES PATENTS 1,486,552 3/1924 Swanson 292-150 2,117,715 5/1938 Godfried -149 2,427,040 9/1947 Billman 29274 RICHARD E. MOORE, Primary Examiner R. L. WOLFE, Assistant Examiner U.S. Cl. X.R. 292-146, 216 

